"We have someone out there that is armed, it is a dangerous situation," Alfonso said.
When paramedics arrived, many of those who had been shot were lying in the street. Lt. Ignatius Carroll with Miami Fire Rescue said the scene was chaotic.
Six people were taken to trauma units and another person went to a hospital with less severe injuries, Carroll said.
"Anytime anybody goes to the trauma center, it's a serious injury," he said.
Dozens of police cruisers swarmed the area and blocked off streets after the shooting.
Authorities didn't immediately release the identities of any of the shooting victims, but did say none were children.
Liberty City's name comes from a housing project built in the 1930s for poor African-Americans and is known around Florida for its crime and grinding poverty. The median household income hovers around $18,000 a year, some $30,000 less than the U.S. average.
The city is also known for riots.
In 1979, a black insurance agent was beaten to death by white and Hispanic police officers. An all-white jury acquitted them and a three-day riot left 18 dead, countless injured and 850 arrested.
Many of the neighborhood's businesses were destroyed, then rebuilt.
Then in 1989, police killed another black motorist, and rioters spewed into the streets just days before the Super Bowl was held in Miami.
The area has never fully recovered. Boarded-up buildings, drug dealers and, recently, foreclosures have mushroomed. Racial tension among blacks, whites, Hispanics and even newer black Caribbean arrivals have simmered for years.
Police are asking anyone with information to call Crime Stoppers at: 305-471-TIPS (8477).
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